(See more in Urban Institute’s Do No Harm Guide)
| Issue | Common Fix |
|---|---|
| Input errors | Cleaning, omitting |
| Unrealistic observations | Sanity checks, filter thresholds |
| Noise/measurement errors | Averaging, interpolation, de-noising |
| Low/heterogenous density | Spatio-temporal aggregation, re-zoning |
| Representativity/biases | Normalization, acknowledgment, additional data collection |